Honda Express spark! then no spark =[

[martynkim]

Seems my points, coil, spark plug wire and boot are all functioning perfectly. There must be something shorting out my connection.



Did you test the rectifier?

[Hondascoots]

Hi I have a few of these, if the points are ok then it is the condensor 99% of the time. Much easier changing that first then trying to chase down a bad wire that may not exist.

[DoubleAey]

okay so no luck so far guys.

i figured maybe the coil was bad? so i got a coil that i knew worked, figuring maybe the current coil wasnt increasing my spark enough to spark the plug. So i got the new one, and took the old condenser off the old coil. Heres some pictures of how i wired it. the thing is, when i use my 6v lighted tester, it lights up when i directly plug it into the black/white wire, and ground it to the head. But when i test it from the sparkplug boot end to the head, i get no light. do i have this wired correctly? OR do i need a new condenser maybe?!?!?! or points? when i turn the flywheel with a drill ratchet the tester lights up beautifully.

[DoubleAey]

-martynkim
the rectifier for the battery connection? i believe its still ok.


-hondascoots
im thinking its the condenser right now too, how much to ship it to california 91387??? its the only part that i knew might be bad, except the points, but i cleaned em, and my tester light lights when they open and close.

[mousewheels]

The coil secondary winding (output to spark plug boot) typically has a high resistance. I went out an looked at the online manual for the Express, but did not find info for the exact resistance. But looking at the Honda Spree and Aero 50, the coils is in the 3k to 8k range. A test lamp implemented with an incandescent bulb will not want to be lighting up on 6v. From ohms law Thats 0.002 amps or less.... A LED based tester could light up, but might notice it being dimmer than a good connection.

Also, there may be a resistor built into the plug cap. For the Aero 50, the specs are 8-8.5k ohms with the cap, and 3.4 to 4.2k with the cap removed.

No spark may be a bad condenser as suggested by hondascoots. Also, the stator coil which drives the ignition coil may be bad. There's some history of those failing on the Express - see http://www.mopedarmy.com and search for Express (edit - Express ignition). I've got a feeling you've done a good job on the points and other sources such as a short to the ign switch are pretty much covered by your test light switching with the points.

--
Ignition problems can be tough. A shorted coil on the ignition coil or stator coil can pass even a resistance test, but kill the spark output. You have swapped in a good ignition coil, so you are rapidly closing in. Condenser is cheap/easy, which puts it as a good next step, but keep the stator coil in mind.

[DoubleAey]

so condenser first, then working stator after. i figured it would be one of the two. =\
ill try an LED light tho, cause i have one i use for testing too, maybe ill get weaker lighting.

hondascoots email me about a condenser,

acbuhay@gmail.com =]


ill keep everyone updated when i try the new condenser.


THANKS!

[DoubleAey]

RAD DUDES! so i got it running.

turns out, it was the points. even after i cleaned them, and filed them, it didnt do the trick. i accidentally over sprayed some liquid wrench onto them, and bam. i had spark. =\

anyways, it runs, i didnt/dont have the spark plug its meant to have, so i put one of my moped spark plugs in, a b8hs, and it runs beautiful. is having that spark plug a bad thing? its running at 23 mph with 4 stroking at WOT but im okay with that for now while im breaking it back into running condition.

has all the covers and stuff on it now, if your wondering how i did the dellorto conversion, is was actually really simple. i had a 21mm minarelli intake that i hacked before hand, so i cut it up a bit more so i only had the end and a little bit sticking out, i then dremeled the the dell out a little to get rid of the shim and to open it up a little. i went to my local department store and bought a small two sided threaded short metal pipe, which i screwed into the end of the dell, i jb welded it closed to get rid of air leaks, and attached it to the intake using a radiator hose and clamps.
works like a charm.

the kick start was super easy... i didnt install the spring, just installed the kick lever a little higher, and when i want to start it, i flicked that started and =D yay.

i found the oil pump does work but leaks, so i just plugged the tube and kept the premix in. all done! Thanks to everyone that helped me out!

http://www.youtube.com/watch?v=Dil2Gddt-HA

[martynkim]

Good Job Fill that tube up with oil by disconnecting it from the tank and fill it from the top. That should get it going also, check the filter inside the tank. If not I got one you can have cheap.

[Wheelman-111]

Greetings:

Nice job finding and correcting the issue. So that you may not encounter more trouble down the road:

i found the oil pump does work but leaks, so i just plugged the tube and kept the premix in. all done!

Legend holds that the pump itself needs oil flowing to self-lubricate. Without any oil coming in, there is reportedly a risk of the pump seizing and perhaps taking the crankshaft worm drive out with it. YMMV